Tuning control device for radio



5, 1942- R. s. ALBRIGHT Re. 22,087

TUNING CONTROLLDEVICE FOR RADIO RECEIVERS AND THE LIKE 3 Sheets-Shut 1Original Filed April 143, 1938 1942- R. BfALBIIGHT I Re. 22,087

TUNING CONTROLDEVICE FOR RADIO RECEIVERS AND THE LIKE Original FiledApril 13, 1938 3 Sheets-Sheet 2v ll A4,

May 5, 1942.

' R. B'. ALBRIGHT TUNING CONTROL DEVICE FOR RADIO RECEIVERS AND THE LIKEa Sheets-Sheet s Original Filed April 13, 1938 Reissuecl May 5, 1942TUNING CONTROL DEVICE FOR RADIO RECEIVERS AND THE LIKE Robert B.Albright, Philadelphia, Pa., assignor,

by Television mesne assignments, to Phileo Radio and Corporation,Philadelphia, Pa., a corporation of Delaware Original No. 2,211,041,dated August 13, 1940, pril 13, 1938. Application for reissue April 18,1941, Serial No. 389,258

Serial No. 201,821, A

1'7 Claims.

This invention relates to tuning control devices for radio receivers andthe like, and more particularly to a novel control device for amultibrand radio receiver, that is, a receiver adapted to receivesignals in a plurality of diiferent irequency bands.

One object of the invention is to provide a novel control deviceconstructed and arranged to provide substantially complete push buttoncontrol operation of a radio receiver, particularly a receiver of themulti-band type.

A more specific object of the invention is to provide a radio receivingsystem which may be tuned in the usual manner by varying the setting ofthe tuning elements and which may also be tuned by means of a pushbutton control mechanism, and to provide means for automaticallyextinguishing the usual dial lamp whenever push button operation isinitiated.

Another object of the invention is to provide push button control meansfor adapting the radio receiver for the reception of signals in aselected frequency band or for the reception of a particular channel,the several control means being both mechanically and electricallyinterlocked to avoid deleterious capacity effects of certain parts ofthe mechanism.

A further object of the invention is to provide in combination with thepush button controls abovementioned a further push button control forthe off and on switch controlling the energization of the receiver, thispush-button controlled switch functioning cooperatively with the otherpush-button controls as described more 'fully hereinafter.

Other objects and features of the invention will be apparent as thedescription proceeds.

In the accompanying drawings:

Fig, 1 is a diagrammatic illustration of a multiband superheterodyneradio receiver embodying one form' of the novel control mechanism of theinvention.

Fig. 2 is a plan view of the switching mechanism employed;

Fig. 3 is a sectional view taken along line 3-3 of Fig. 2;

Fig. 4 is a fragmentary perspective view of a switch element;

Fig. 5 is a perspective view of a radio receiver embodying the controlmechanism;

Fig. 6 is a diagrammatic illustration of another embodiment of theinvention;

Fig. 7 is a plan view of the switch mechanism thereof; and

Fig. 8 is a perspective view of a special contact strip employed in thisdevice.

Referring to Fig. 1 there is shown an antenna A which supplies theincoming signals to the usual detector-oscillator 0, from which thesignal energy passes through the usual successive stages of theconventional superheterodyne receiver including an intermediatefrequency amplifier IF, 2. double diode-triode detector D, an audiofrequency amplifier AF, and the usual loud speaker LS. The manner inwhich such a receiver operates is well understood, and it is, therefore,unnecessary to refer to the operation further than is necessary todescribe the control mechanism of the invention.

The radio receiver illustrated is supplied with electrical energy bymeans of the usual power supply system including transformer T, rectiherR, and filter F. The energization of the receiver is controlled in aparticular manner, however, by the push button control mechanism, aswill be described later.

For manual tuning of the receiver, there are provided the ganged tuningcondenser TC and T01 which serve to vary the tuning of the circuitsassociated with the detector-oscillator stage, as will be Wellunderstood. To enable manual tuning of the receiver, the usual tuningdial of some suitable form will be provided and a dial lamp L will becooperatively associated with the tuning dial to facilitate manualtuning in accordance with common practice. The dial mechanism is notshown in Fig. 1, since the construction and manner of operation of sucha mechanism is well understood. The dial lamp L, however, plays a partin the practice of the present invention, as will be explainedpresently.

The radio receiver illustrated is of the multiband type, and inaccordance with common practice there are provided selectable channels,BC and SW, for transferring signals in the diiferent wave bands from theantenna A to the detectoroscillator O. The oscillator circuits BC and SWare also adapted for operation in the same frequency bands. In anysystem of this character, some suitable means are provided for selectingone of the channels and for connecting the oscillator circuitsaccordingly. In the presentinstance, the necessary switching operationsto adapt the receiver for operation in the selected frequency bands areeffected by means of the push button control mechanism now to bedescribed. In addition, this mechanism controls the connection of thetuning condensers TC and TCL. Hence, the receiver may be adapted for theusual manual adjustment tuning or for push button tuning.

The push button control mechanism provided by the invention comprisestwo groups of switches constructed and arranged for operation in pairsby push buttons; that is to say, the switches of one row or groupcorrespond to the switches of the other row, and corresponding pairs ofswitches are arranged for tandem operation, each such pair of switchesbeing operated by a single push button. In Fig. 1, the switches areillustrated diagrammatically in correspondence to the mechanicalstructure shown in Figs. 2 to 4 and described hereinafter.

The two switches Ss and S's serve to control the short wave bandconnections, while the switches Sb and S's serve to control thebroadcast band connections. These two pairs of switches are operatedrespectively by the push buttons PS and Pb, the tandem operation of theswitches being designated by the broken line connections.

The switches S1, S2 andSz, etc., and the associated switches S1, S2, S3,etc. serve to control the tuning of the radio receiver to predeterminedsignalsinthe broadcast band, the respective pairs of these switchesbeing operated by the push button elements P1, P2, P3, etc. It will benoted that the switches S1, S2, S3, etc. control the connectionof tunedcircuits including the condensers C1, C2, G3, etc., while the switchesS1, S2, S3, etc. control the connection of tuned circuits including thecondensers C1, C2, C3, etc.

The switches S and S, operated by the element P control the energizationof the radio receiver, these switches being serially connected in theprimary circuit of the power transformer T.

The various push button-controlled switches are generally similar instructure, at least to the extent that each comprises a plurality ofstationary contacts designated by the small circles and the permanentconnections therebetween, and a movable contact member carrying aplurality of contacts, designated by arrow heads, which engage thestationary contacts. As will be described in further detail later, acommon latch bar LB serves to latch any one of the push button elementsin depressed position, and is arranged so that the actuation of anyother element releases the previously-depressed element. Consequently,at any one time, only one of the push button elements will be indepressed position.

It will be noted that the switches S and S' are open when the pushbutton element P is depressed and are closed when this element is innon-depressed position. Therefore, in order to deenergize the radioreceiver, push button P is depressed to open the switches S and S.Assuming that the radio receiver is thus deenergized, when any one ofthe other push buttons is depressed to operate the receiver, the pushbutton P is automatically released and moves to switchclosing position,so that the receiver is automatically energized.

It will be noted further that the energizing circuit for the dial lamp Lincludes the back contacts of switches S1, S2, S3, S4 and S5. Therefore,the dial lamp is energized only when all of the push-buttons P1, P2, P3,P4 and P5 are in nonactuated position. When any one of these stationselecting push buttons is depressed, however, the energizing circuit ofthe dial lamp L is opened, so that the lamp is deenergized during pushbuttonstation selecting operation. At such time, the tuning dial is notemployed and the illumination of the dial is unnecessary. This featureof the invention gives an indication of the condition of adjustment,prolongs the life of the dial lamp, and effects an economy in thecurrent consumption of the lamp.

When the channel-selecting switches are in the positions shown, thereceiver is adapted for push button operation in the broadcast range,for the broadcast channels BC and BC are completed, the tuningcondensers TC and T01 are disconnected, and the circuits of the pushbutton-controlled condensers are connected to the signal channel. Theseconnections obtain by reason of the connection of the conductor b, thegrid lead e and the common connector cl for the switches S1, S2, etc.and the corresponding connection of the oscillator connections. Theactuation of any one of the station selecting push buttons P1, P2, P3,etc. will close the corresponding tuned circuits, thus tuning thereceiver to the particular broadcast signal represented by the actuatedpush button. Diiferent signals in the broadcast band may be receivedsuccessively by successive operationofthestation selecting push buttons.During the entire operation of the radio receiver, the push button Pwill remain in non-actuated position, so that the receiver will beconstantly energized. When it is desired to deenergize the receiver, thepush button P is depressed to open the switches S and S.

Preferably, there is provided a lamp L1 arranged cooperatively with thepush button mechanism for indicating the condition of the push buttonsin any instance. For example, an arrangement such as shown in thecopending application of Leslie J. Woods, Serial No. 179,602, filedDecember 13, 1937 may be employed to indicate the operative push buttonin any instance as distinguished from the non-actuated push buttons. Forthe purpose of the present application, it suffices to state that sucharrangement employs one or more lamps as a source of illumination forthe push button indicators. The lamp L1 which is constantly energized bytransformer T is representative of such sourcev When it is desired tomanually tune the radio receiver to stations in the broadcast band byadjustment of the tuning condensers TC and T61, the push button Pb isdepressed, which causes connection of the tuning condensers TC and T01,or in other words connection of leads b, c and e and the correspondingoscillator connections. At the same time, the dial lamp circuit isenergized.

When the operator desires to receive signals in the short wave band, hedepresses the push button P5, causing the releaseof push button Pb. Theshort wave switches SS and SS disconnect the broadcast band connectionsand connect the short wave channel SW to the input circuit of tube 0 andalso connect the short wave circuit SW. The tuning condensers TC and TClare also connected to the signal channel for operation. In other words,leads a, c and e are connected together and the corresponding oscillatorleads are connected. In thi instance also, the dial lamp will beilluminated and the receiver may be manually tuned in the customarymanner, by adjusting the tuning condensers.

The push button mechanism preferably is constructed as illustrated inFigs. 2 to 4. A pair of spaced insulating strips Ii.) and H serve tosupport the stationary contact elements of the respective groups ofswitches, these contact elements being in the form offlexible metalstrips which are inserted through openings inthe in sulating strips andbent to secure them in place. To simplify the manufacture of thestructure, each of the insulating strips may have punched therein aplurality of similar sets of holes, one set for each switch. Each set ofholes consists of three rows of three holes each making a total of nineholes for each switch, as may be seen in Fig. 2. While some of theseholes are not used, it is cheaper to punch similar sets of openings bymeans of similar punches than it would be to punch different sets ofopenings employing different punches. The manner in which the metalstrips are inserted in the holes of the insulating strips and bent maybe seen from the sectional view of Fig. 3 wherein it will be seen thatthe strips 12 are inserted through the rear holes and then through theintermediate holes and have their forward ends I3 bent over to securethem in place. portions Hi which are engaged by spring fingers l5carried by the associated plunger or push button element and insulatedtherefrom by means of insulating blocks Hi. The manner in which the rearend of a plunger or push button element, is constructed to provide thewiping contacts is illustrated in Fig. 4. The insulating strips and IIare carried by a wall I! which is secured to the front wall I8 by meansof brackets I9.

The spring finger wiper at the bottom of each push button element andthe lower set of stationary contacts engaged by such wiper constitutesone switch of a pair, while the upper wiper and the upper set ofcontacts engaged thereby constitutes the other switch of the pair. Inthis manner, the switches are arranged in pairs, each pair of switchesbeing operated by a single push button element as described above inconnection with Fig. 1.

Referring to Fig. 2 and considering the manner in which the variousswitches and their connections are formed, it will be seen that each ofthe switches S5 and 85, comprises a strip 20 which is inserted through arear hole and then through the corresponding front hole with its end 2|bent over as illustrated. This switch also comprises strips 22 and 23,as illustrated. The associated switches Sb and St are similarly formed,each comprising a long strip 24 corresponding to strip 20 and two shortstrips 25 and 25 corresponding to strips 22 and 23. The adjacent frontholes of the two switch section support a connecting strip 21.

Each of the ten station selecting switches S1, S1, S2, S2, etc.comprises two contact strips 28 and 29 inserted through the rear andintermediate openings of the outer rows of holes, as shown in Fig. 2.The switches S1, S2, S3, S4, and S5 are also connected together by linkstrips 30, 3|, 32 and 33. The switches S1 and S5 are further providedwith terminal links 34 and 35. These connecting links and terminalsprovide for the series connection of the switches in the dial lampcircuit, as illustrated in Fig. 1.

The switches S and S each comprises a pair of contact strips 36 and 31which are inserted through the intermediate and front openings of theouter rows of holes, as shown in Fig. 2. These switches are thusconstructed so that they are closed when the push button P is in itsouter or non-actuated position.

Each of the push button elements comprises a rod 38 slidably carried bythe spaced walls l1 and 18. Each of these elements is urged to its outeror 'nonactuated position by a spring 39 disposed between the wall l1 anda lug or pro- There are thus provided jection 40 on the push rod. Thelatch bar LB above mentioned is pivotally carried by the brack ets l3and is urged in the counter-clockwise direction, as viewed in Fig. 3, bythe leaf spring 4|. Each of the push rods has a shoulder detent 42,formed therein for cooperation with the latch bar to hold a depressedpush rod in latched position against the action of its spring, as shownin Fig. 3. There is also formed on each push rod a cam face 43 whichdeflects the latch bar when the push button element is actuated. Thisreleases any previously depressed push button element. Each of the pushrods carries at its outer end a head 44 which may be actuated by afinger of the operator, the front face of the head preferably beinginclined or slanted as illustrated.

In Fig. 5, there is illustrated a small radio receiver embodying thepush button mechanism which is mounted above the speaker grill 45. Thepush button elements extend through an inclined panel 46 and directlyabove the push buttons, there is a straight dial 41, the pointer ofwhich moves back and forth across the dial as the tuning knob 43 ismoved in its slot 49, as will be well understood. The knob 48 is movedto tune the receiver manually in the usual manner when it is not desiredto employ the push buttons. During this manual tuning, the dial lampassociated with the dial 4! will be illuminated, but when the pushbutton operation is initiated, the dial lamp is extinguished asdescribed above.

In Figs. 6 and 7, there is illustrated an alternative form of the pushbutton control mechanism. Fig. 6 shows a portion of the multi-bandreceiver and the control mechanism associated therewith, the push buttoncontrol switches being shown in a slightly different manner from thoseof Fig. l. The small circles represent the stationary contacts of theswitches while, in each instance, the movable contact of a switch isshown as a contact bar which is adapted to engage one or the other ofthe two rows of contacts, depending upon whether the push button is innonactuated position or in actuated position. Here again, the switchesand SS control the operation of the receiver in the short wave band,while the switches Sb and St control the operation in the broadcastband. The switches S1 and S2 and their companion switches S1 and S2 arethe station-selecting switches for use in the broadcast band. While onlytwo sets of station-selecting switches are illustrated, any number ofthese switches may be employed. Further, although the two rows ofswitches are represented as separate rows of push button switches, theyshould preferably be arranged for operation in pairs, each pair ofswitches being controlled by a single push button, as described above inconnection with Fig. 1.

The operation of this device is generally similar to the operation ofthe device of Fig. 1 and. will be readily understood. In this instancealso the station-selecting switches may control the energization of thedial lamp so that the dial lamp will be extinguished during push buttontuning as above described, although the dial lamp circuit is notcompletely illustrated in Fig. 6. It will be understood also that theenergization of the receiver may be controlled by a pushbutton switch inthe manner illustrated in Fig. l.

The push-button-controlled switches in Fig. 6 may be constructed in thesame manner as described above in connection with the mechanicalstructures shown in Figs. 2 to l. In Fig. 7, there is shown a plan viewof one of the insulating strips and the stationary contacts carriedthereby for forming one of the rows of switches. Each of the short waveswitches comprises contact strips 50, 53 and 54 carried by theinsulating strips Each of the broadcast band switches comprises a longcontact strip 55 inserted in the center row of holes and short contactstrips 56 and 51 inserted in the two outer rows of holes. A connectingstrip 58 is arranged as illustrated to connect the two adjacent waveband switches in the manner shown in Fig. 6.

Each of the station-selecting switches S1 and S1 comprises a contactstrip 59 and a special contact strip 60 (see Fig. 8), the portion 6| ofwhich is obliquely disposed and serves as a connecting link between thefirst station-selecting switch and the broadcast band switch, asillustrated in Fig. 6. This contact strip has a turned up lug 62 whichextends through one of the panel openings and is turned over to anchorthe inter- 'mediate part of the strip.

Each of the other station selector switches comprises strips 62 and 64arranged as illustrated. The strips 65, B6 and 61 may be employed tocontrol the dial lamp circuit.

Referring to both Fig. 1 and Fig. 6, to eliminate the need for anadditional switch to disconnect the BC transformer during short wavereception, the primary of said transformer is shunted by a condenser thevalue of which is such as to tune the primary coil to a frequencyslightly below the broadcast band. This condenser serves to by-pass theprimary coil to high frequencies so that switching is unnecessary.

It will be appreciated that one purpose of the switching arrangementherein disclosed is to connect the leads I), d and e (Figs. 1 and '6) totune preselected stations, to connect the leads I), c and e for manualtuning in the broadcast band, and to connect a, c and e for manualtuning in the short wave band.

Further, it is desirable to eliminate the detrimental efi'ect of thecapacity to ground of the common lead d. This capacity is shown by thedotted condenser Cg. It will be understood that this capacity is presenteven though switches S1 to S5 are open and hence some means must beprovided to disconnect this lead from the circuit.

In the circuit of Fig. 1, this is accomplished on the short wave band,by the series connections of d to e through the back contacts of Ss.Hence when P5 is depressed the lead d is disconnected from the tunedcircuit and the grid lead e is connected only to a and c. shunting ofthe tuned circuit on the short wave band by the capacity to ground of dis thusavoided.

In the circuit of Fig. 6, this principle is extended to operate in bothwave bands. In this figure the series connection includes the backcontacts of both SS and Sb. Hence, if PS is depressed, the grid lead eis connected only to a and c and d is disconnected from the circuit, andif Pb is depressed, grid lead 6 is connected only to b and c and d isagain disconnected. However, if a button P1, etc. is depressed then bothPS and Pb will be returned to their normal positions and d is connectedto e and I) through the back contacts of both 55 and Sb.

It will be apparent that in both Figs. 1 and 6, it is necessary toconnect d to e and b when both S5 and S5 are in the normal position. InFig. 6 this is done by a circuit which disconnects d from the tunedcircuit when either P5 or Pb is depressed. However, this arrangementrequires the use of the special shaped connector of Fig. 8 oralternatively an extra external connection. By only disconnecting d fromthe tuned circuit in short wave reception as shown in Fig. 1, standardparts may be used which makes for economy but less satisfactory results.

From the above description, it will be seen that the invention providesa novel control device for a radio receiver or the like wherein aminimum of parts are used to obtain certain novel and desirable resultswithout the addition of complexity or cost, and by means of which thereceiver may be operated to receive signals in different wave hands byselective operation of push button elements, and the receiver may betuned to stations in one of the frequency bands by means ofstation-selecting push button elements or the receiver may be tunedmanually in the usual manner to stations in each of the frequency bands.Furthermore, the device :automatically controls the energization of theusual dial lamp according to whether the receiver is tuned by means ofthe push buttons or .by means of the tuning condensers. While twoembodiments of the invention have been illustrated and described for thepurpose of disclosure, it will be understood that the invention iscapable of further modifications without departing from its scope asdefined by the appended claims.

I claim:

1. In a radio receiver having tuning means including a dial and diallamp, means operable at will for tuning said receiver to any one of aplurality of predetermined signals of different frequencies, said meansincluding a plurality of selectable manually-operable elements, and aplurality of serially-connected switches in circuit with said lamp andoperable respectively by said elements, each of said elements beingconstructed and arranged to close the associated lamp-control switchwhen in non-actuated position and to open the switch when in actuatedposition, whereby said dial lamp is rendered inoperative whenever anyone of said elements is actuated and is rendered operative whenever allof said elements are in non-actuated position.

2. In a radio receiver having tuning means inincluding a dial and diallamp, means operable at will for tuning said receiver to any one of aplurality of predetermined signals of different frequencies, including aplurality of tuned circuits for adapting said receiver for reception ofsaid signals, a plurality of switches for selecting said tuned circuits,a plurality of selectable manuallyoperable elements constructed andarranged to close said switches when moved to actuated position, and aplurality of serially-connected switches in circuit with said lamp andoperable respectively by said elements, each of said elements beingconstructed and arranged to close the associated lamp-control switchwhen in nonactuated position and to open the switch when in actuatedposition, whereby said dial lamp is rendered inoperative whenever anyone of said elements is actuated and is rendered operative whenever allof said elements are in non-actuated position.

3. In a radio receiver having tuning mean including a dial and diallamp, an energizing circuit for said lamp, means operable at will fortuning said receiver to any one of a plurality of predetermined signalsof different frequencies, including a plurality of tuned circuits foradapting said receiver for reception of said signals, and a plurality oftwo-position switches one for each of said tuned circuits, each of saidswitches being constructed and arranged to select its associated tunedcircuit when moved to one position, and to close contacts seriallyincluded in the lampenergizing circuit when moved to its other position,whereby said dial lamp is rendered inoperative whenever any one of saidswitches is moved to its circuit-selecting position and is renderedoperative whenever all of said switches are in their other position.

4. In a radio receiver, a tuning condenser, a plurality of coils tunableby said tuning condenser to wave signals in different frequency bands, adial and dial lamp for indicating the tuning of the receiver, a signaltransfer channel, a plurality of adjustable tuning elements, a pluralityof switches constructed and arranged to select said tuning elements andto render said lamp inoperative whenever one of said elements isselected, a common connector for said switches, and means including atleast one two-position switch for connecting said common connector andone of the coils to said channel, or alternatively connecting saidtuning condenser and a selected one of said coils to said channel, meansfor latching any one of the aforesaid switches in actuated position, andmeans for moving an actuated switch to non-actuated position wheneveranother switch is actuated,

5. In a radio receiver, a tuning condenser, a coil tunable by saidtuning condenser to wave signals in a certain frequency band, a, signaltransfer channel, a plurality of adjustable tuning elements, a pluralityof switches connected respectively to said tuning elements for selectiveoperation thereof, a common connector for said switches, a two-positionswitch constructed and arranged to connect said tuning condenser andsaid coil to said transfer channel when in actuated position, and toconnect said coil and said common connector to said channel when innonactuated position, means for latching any one of the aforesaidswitches in actuated position, and means for moving an actuated switchto nonactuated position whenever another switch actuated.

6. In a radio receiver, a tuning condenser, a coil tunable by saidtuning condenser to wave signals in a certain frequency band, a spacedischarge device having an input element, a plurality of pretunablecircuits including adjustable tuning elements, a plurality of switchesconnected respectively to said tuning elements for selective operationof said pretunable circuits, a common connector for said switches, meansincluding a two-position switch for conecting said tuning condenser andsaid coil to said input element, or alternatively connecting said commonconnector to said input element, means for latching any one of theaforesaid switches in actuated position, and means for moving anactuated switch to non-actuated position whenever another switch isactuated.

"I. In a radio receiver, a tuning condenser, a plurality of coilstunable by said tuning condenser to wave signals in different frequencybands, a signal transfer channel, a plurality of adjustable tuningelements, a plurality of switches connected respectively to said tuningelements for selective operation thereof, a common connector for saidswitches, a plurality of two-position switches correspondingrespectively to said coils, and movable selectively from nonactuatedposition to actuated position, said twoposition switches beingconstructed and arranged til to connect said common connector and one ofthe coils to said channel when the two-position switches are innon-actuated position, and to connect said tuning condenser and one ofthe coils to said channel and disconnect said common connector when oneof the switches is moved to actuated position, means for latching anyone of the aforesaid switches in actuated position, and means for movingan actuated switch to nonctuated position whenever another switch isactuated.

8. In a radio receiver, a tuning condenser, a plurality of coils tunableby said tuning condenser to wave signals in different frequency bands, asignal transfer channel, a plurality of adjustable tuning elements, aplurality of switches connected respectively to said tuning elements forselective operation thereof, a common connector for said switches, meansincluding at least one two-position switch for connecting said commonconnector and one of the coils to said channel or alternativelyconnecting said tuning condenser and a selected one of said coils tosaid channel, means for latching any one of the aforesaid switches inactuated position, and means for moving an actuated switch tonon-actuated position whenever another switch is actuated.

9. In a multi-band radio receiver, a tuning condenser, a plurality ofcoils tunable by said tuning condenser to wave signals in differentfrequency bands, a space discharge device having an input element, aswitch constructed and arranged to connect one of said coils, saidtuning condenser and said input element in shunt relation with oneanother when the switch is in actuated position, another switchconstructed and arranged to connect another of said coils, said tuningcondenser and said input element in shunt relation with one another whenthe switch is in actuated position, a plurality of adjustable tuningcondensers, a plurality of switches connected respectively to saidlast-mentioned condensers for rendering such condensers selectivelyoperable, a common connection for said last-mentioned switches, aconnection through at least one of said first-mentioned switches in itsnon-actuated position for connecting said common connection to one ofsaid coils and to said input element, means for latching any one of saidswitches in actuated position, and means for moving an actuated switchto non-actuated position whenever another switch is actuated.

10. In a multi-band receiver, a tuning condenser, a plurality of coilstunable by said tuning condenser to' wave signals in diiferent frequencybands, a signal transfer channel, a plurality of pretunable elements, aplurality of switches each having a normal and an'actuated position andeach connected to said pretunable elements and to a common connection, afirst wave band switch having a normal and an actuated position,connections to said first wave band switch for con necting said tuningcondenser and one of said coils to said signal channel when said switchis in actuated position, a second wave band switch having a normal andan actuated position, connections to said second wave band switch forconnecting said tuning condenser and the other of said coils to saidsignal channel when said second switch is in actuated position,connections to both of said switches for connecting said signal channeland one of said coils to said common connection when both of said waveband switches are in normal position, and for disconnecting said commonconnection from said signal channel when one of said wave band switchesis actuated; and a mechanical interlock for moving the other of saidswitches to normal position when any one of said switches is moved toits actuated position.

11. A radio receiver having a first tuning means including a dial anddial lamp for tuning said receiver to wave signals in differentfrequency bands, at second tuning means operable at will for tuning saidreceiver to any one of a plurality of predetermined signals within onewave band, said first tuning means including a first group of selectablemanually operable elements, said second tuning means including a secondgroup of selectable manually operable elements, and means forautomatically rendering one of said tuning means inoperative wheneverthe other tuning means is actuated.

12. A radio receiver having a first tuning means for tuning saidreceiver to wave signals in different frequency hands, a second tuningmeans for tuning said receiver to any one of a plurality ofpredetermined signals, said first tuning means including a first groupof selectable manually operable elements, said second tuning meansincluding a second group of selectable manually operable elements, andelectric circuit means for automatically rendering one of said tuningmeans inoperative whenever the other tuning means is actuated.

13. A radio receiver having a first tuning means for tuning saidreceiver to wave signals in different frequency bands, a second tuningmeans operable at will for tuning said receiver to any one of aplurality of predetermined signals within one wave band, said firsttuning means including a first group of selectable manually operableelements, said second tuning means including a second group ofselectable manually operable elements, and electric circuit means forautomatically rendering one of said tuning means inoperative wheneverthe other tuning means is actuated.

14. A multi-band radio receiver, comprising selectable circuit means forthe reception of signals in different frequency hands, a plurality ofpush-button operated switches for selectively controlling said circuitmeans, a plurality of selectable pretuned elements for tuning thereceiver to predetermined signals in a particular wave band, arelatively high capacity common circuit connector for said elementsadapted to be completed by said switches in their non-actuatedpositions, a plurality of push-button operated switches for selectivelyconnecting said pretuned elements to said common connector, and meansfor maintaining any one of the aforesaid push-button switches inoperated position, and for releasing any operated switch wheneveranother switch is actuated, said first switches serving to disconnectsaid high capacity common conductor when the same is not in use.

15. In a radio receiver, a plurality .of pushbutton elements selectivelydepressible for operation of the receiver in different frequency bandsone of which is the broadest band, circuit means rendered operative onlywhen one of said elements is depressed to condition the receiver formanual tuning within the frequency band to which the depressed element;corresponds, a plurality of push-button elements corresponding topreselected frequencies in the broadcast band, interlocking circuitmeans rendered operative only when the first-mentioned push-buttonelements are in non-actuated position and operable by saidlast-mentioned push-button elements to tune the receiver automaticallyto one of said preselected frequencies, and interlocking mechanicalmeans for restoring any depressed pushbutton element to its non-actuatedposition whenever any other push-button element is depressed, wherebythe receiver may be conditioned for manual tuning in any one of saidfrequency bands or may be tuned automatically to a preselected frequencyin the broadcast band by the actuation of a single push-button element,

16. In a radio receiver, a plurality of pushbutton elements selectivelydepressible for operation of the receiver in different frequency bands,manual tuning means for said receiver, circuit means controlled by saidpush-button elements for rendering said tuning means operative only whenone of said elements is depressed, thereby to condition the receiver formanual tuning within the frequency band to which the depressed elementcorresponds, a plurality of push-button elements corresponding topreselected frequencies within one of said frequency bands, pretunedelements selectable by said lastmentioned push-button elements forautomatically tuning the receiver to said preselected frequencies insaid one band, interlocking circuit means for rendering said pretunedelements operative only when the first-mentioned push-button elementsare in non-actuated position, and interlocking mechanical means forrestoring any depressed push-button element to its non-actuated positionwhenever any other push-button element is depressed, whereby thereceiver may be conditioned for manual tuning in any one of saidfrequency bands or may be tuned automatically to one of said preselectedfrequencies by the actuation of a single push-button element.

17. In a radio receiver, a plurality of pushbutton switches selectivelydepressible for operation. of the receiver in different frequency bands,said switches having contacts at their non-actuated and actuatedpositions, circuit means controlled by the contacts at the actuatedpositions of said switches to condition the receiver for manual tuningwithin the frequency band to which the actuated switch corresponds, aplurality of push-button switches corresponding to preselectedfrequencies within one of said frequency bands, pretuned elementsselectable by said last-mentioned switches for tuning the receiverautomatically to said preselected frequencies, a common circuitconnector for said elements connected to the contacts at the nonactuatedpositions of said first-mentioned switches so as to render said elementsoperative only when said first-mentioned switches are in non-actuatedposition, and means for restoring any actuated one of the aforesaidswitches to its non-actuated position whenever any other switch isactuated, whereby the receiver may be conditioned for manual tuning inany one of said frequency bands or may be tuned automatically to one ofsaid preselected frequencies by the actuation of a single push-buttonswitch.

ROBERT B. ALBRIGHT.

